Bridge/Extender/Repeater for multiple SSIDs with different subnets

I found some other posts that seem to cover my issue, but I was not able to decipher them enough to get things working. This feels just beyond my understanding of networking, so I'm having a hard time understanding all the pieces of the puzzle. If anyone is feeling patient enough to break it down for me, I would be very grateful.

My main home router is a new Netgear R7000 running Advanced Tomato 138. I have 3 VLANs

VLAN 1 - 192.168.1.0/24 - main, private home network (both 2.4 and 5...

Bridge/Extender/Repeater for multiple SSIDs with different subnets